Currently, a curved display device with a curved display surface has become a popular tendency, and a screen of the curved display device is in a shape of arc. However, a viewing angle of the curved display device is small, and thus the curved display device is only suitable for being viewed by a few people, and is not applicable in the case that it is viewed by many people. Thus, some bendable display devices are generated; and the bendable display device is bendable to be in the shape of arc so as to make the screen thereof freely switched between a plane state and a curved state with a small curvature.
In the bendable display device, four corner portions of a circuit board card are fixed to positioning columns of a backplate. In the case the bendable display device is bent into the shape of arc, a bending performance of the circuit board card is very bad and the circuit board card tends to keep flat, and therefore a relatively great interaction force is generated between the circuit board card and the bent backplate, and a force from the bent backplate on the circuit board card acts on the circuit board card through the positioning columns at the four corner portions. In the case the bendable display device is bent, the circuit board card bears the force of the positioning columns all the time till the bendable display device resumes to be a flat panel display device. Thus, in the bendable display device, the circuit board card is damaged quite easily, which thus causes defect.